Proximity information devices, such as proximity (or “contactless”) payment devices, cards or keyfobs, are becoming increasingly common. Proximity information devices commonly use a magnetic field (generated by a point of sale terminal, for example) to activate a proximity device. Once activated, information and data may be transmitted between the proximity device and the point of sale terminal.
One concern that has been raised about these devices is that it may be possible for unauthorized persons to surreptitiously read private information from proximity information devices by activating the proximity device from a greater distance than normally achieved with a conventional reader. For example, an unauthorized person may carry or set up a device that uses greater transmitter power than permitted for such devices and other refinements to increase operational range. It is widely understood that given sufficient resources, a device can be constructed that is capable of communicating with a proximity information device over a distance of up to 1 meter. It has been reported by some that devices have been constructed that allow communication at a distance of up to 10 meters.
An unauthorized person may use such a device in an attempt to capture the payment card information from proximity payment cardholders in a busy environment. While other security techniques prevent these attacks from using the financial data from the cards, many users are concerned about the privacy issues associated with such attacks. Similar concerns exist for other types of proximity information devices such as contactless drivers licenses, medical cards, identification cards and passports.
A number of proposals have been made to provide a user-actuated switch on proximity information devices so that the device may be carried in an unactivated state until the device is to be used to conduct a transaction.
A possible disadvantage of proposed designs for a proximity information device having a user-actuatable switch is that the manufacturing cost of the device may be increased by incorporating a switch in the device. Also, some users may prefer not to have to actuate a switch while presenting their proximity information device for reading.